"If you ask someone on the street what arousal means, that person might have an intuitive concept of arousal in terms of sexual excitement, alertness or an emotional response such as fear," says Pfaff, professor and head of the Laboratory of Neurobiology and Behavior at Rockefeller. "But, if you ask, 'Exactly what does arousal mean scientifically,' it's been very hard for scientists to pin down."
Scientists who study arousal historically were divided into two camps: those who consider arousal to be a single, "monolithic" physiological function, and those who believe that arousal does not exist as a whole, but is a collection of small specific abilities.
In the PNAS paper, Pfaff and colleagues present a mathematical equation that for the first time unifies these two disparate schools of thought and combines generalized arousal with various specific forms of arousal, such as sex, hunger and fear. They also show that experiments can be designed to measure arousal in laboratory mice, which ultimately will provide genetic answers to the question "what is arousal?"
In humans, deficits in arousal contribute to such cognitive problems as attention deficit hyperactivity disorder, autism and Alzheimer's disease. Erosion of arousal also may account for some of the mental difficulties that people face as they age. Understa
Contact: Joseph Bonner